The University of Southampton
University of Southampton Institutional Repository

Modification of fetal plasma amino acid composition by placental amino acid exchangers in vitro

Cleal, Jane K., Brownbill, Paul, Godfrey, Keith M., Jackson, John M., Jackson, Alan A., Sibley, Colin P., Hanson, Mark A. and Lewis, Rohan M. (2007) Modification of fetal plasma amino acid composition by placental amino acid exchangers in vitro The Journal of Physiology, 582, (2), pp. 871-882.

Record type: Article

Abstract

Fetal growth is dependent on both the quantity and relative composition of amino acids delivered to the fetal circulation, and impaired placental amino acid supply is associated with restricted fetal growth. Amino acid exchangers can alter the composition, but not the quantity, of amino acids in the intra- and extracellular amino acid pools. In the placenta, exchangers may be important determinants of the amino acid composition in the fetal circulation. This study investigates the substrate specificity of exchange between the placenta and the feto-placental circulation. Maternal-fetal transfer of radiolabelled amino acids and creatinine were measured in the isolated perfused human placental cotyledon. Transfer of L-[14C]serine or L-[14C]leucine, and [3H]glycine, were measured in the absence of amino acids in the fetal circulation (transfer by non-exchange mechanisms) and following 10-20 micromol boluses of unlabelled amino acids into the fetal circulation to provide substrates for exchange (transfer by exchange and non-exchange mechanisms). The ability of fetal arterial boluses of L-alanine and L-leucine to stimulate release of amino acids from the placenta was also determined using HPLC in order to demonstrate the overall pattern of amino acid release. Experiments with radiolabelled amino acids demonstrated increased maternal-fetal transfer of L-serine and L-leucine, but not glycine, following boluses of specific amino acids into the fetal circulation. L-[14C]Leucine, but not L-[14C]serine or [3H]glycine, was transferred from the maternal to the fetal circulation by non-exchange mechanisms also (P<0.01). HPLC analysis demonstrated that fetal amino acid boluses stimulated increased transport of a range of different amino acids by 4-7 micromol l(-1) (P<0.05). Amino acid exchange provides a mechanism to supply the fetus with amino acids that it requires for fetal growth. This study demonstrates that these transporters have the capacity to exchange micromolar amounts of specific amino acids, and suggests that they play an important role in regulating fetal plasma amino acid composition.

PDF 48461.pdf - Version of Record
Restricted to Repository staff only
Download (555kB)

More information

Published date: 3 May 2007
Keywords: amino acid transport, fetus, flacenta
Organisations: Dev Origins of Health & Disease, Medicine

Identifiers

Local EPrints ID: 48461
URI: http://eprints.soton.ac.uk/id/eprint/48461
ISSN: 0022-3751
PURE UUID: 05c029b5-fcf3-4183-8a8b-bfd749bd2a3d
ORCID for Keith M. Godfrey: ORCID iD orcid.org/0000-0002-4643-0618
ORCID for Rohan M. Lewis: ORCID iD orcid.org/0000-0003-4044-9104

Catalogue record

Date deposited: 25 Sep 2007
Last modified: 27 Aug 2017 04:01

Export record

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×